The prior art is well documented with examples of seat recliner devices, and such as which can be incorporated into a vehicle seat whereby the seat back is capable of being rotatably mounted about a crosswise extending hinge defined with the seat bottom. Such circular/rotary disc package arrangements are particularly suited for seating applications, and in order to provide a dependable assembly for incrementally adjusting the seatback relative to the seat bottom, as well as optionally for facilitating dumping of the seatback against the seat bottom.
U.S. Pat. No. 6,854,802, issued to Matsuura et al., teaches a seat recliner having a base mounted to a first seat member. A seal recliner includes a gear mounted to a second seat member and which is rotatable relative to the base. The gear has first teeth along a peripheral face of the gear. The seat recliner includes a locking member movable inside the first teeth and which includes second interengageable teeth. A cam is configured to rotate the locking member to engage the first and second teeth with each other for establishing an angle between the first and second seat members. A guide is located on the base and exhibits a guide face for slidably guiding the locking member to engage the first and second teeth with each other. The guide extends radially from a vicinity of the first teeth to a vicinity of the cam. A near side of the guide relative to the first teeth and the locking member define a gap therebetween.
A further series of related recliner devices are set forth in U.S. Pat. No. 6,648,414 (Ikegaya et al.), U.S. Pat. No. 6,666,515 (Asano et al.) and U.S. Pat. No. 6,629,733 (Matsuura et al.). Each of the above-referenced are architecturally similar to the Matsuura et al. recliner.
Other references worthy of mention include the automotive seat recliner apparatus of Ohba, U.S. Pat. No. 7,144,082, as well as the seat reclining device of Ohba, U.S. Pat. No. 7,150,503. In the specific example of the reclining device of U.S. Pat. No. 7,150,503, a base member is coupled to one of a seat cushion or a seat back, with a gear teethed pivot member being coupled to the other. A shaft member is formed integrally with the base member and has a cylindrical shaft surface. A lock member includes first and second opposite end surfaces, with lock teeth formed in the second end surface. A cam member is provided for moving the lock member to engage the lock teeth with the gear teeth, first and second guide members being formed integrally with the base member to guide the lock member along a path around the shaft member and a stress absorbing protrusion formed integrally with the shaft surface on an opposite side of the shaft member from the lock teeth.